Playing air traffic controller with software defined radio

Being an air traffic controller is a very cool career path – you get to see planes flying around on computer screens and orchestrate their flight paths like a modern-day magician. [Balint] sent in a DIY aviation mapper so anyone can see the flight paths of all the planes in the air, with the added bonus of not increasing your risk of heart attack or stroke.

[Balint]’s Aviation Mapper uses software defined radio to overlay RADAR and ACARS messages from aircraft and control towers in an instance of Google Earth running in a web browser. After grabbing all the radio data from a software defined radio, [Balint]’s server parses everything and chucks it into the Google Earth framework. There’s a ton of info, pictures, and explanations of the inner machinations of the hardware on [Balint]’s official project page.

Right now, Aviation Mapper only displays planes within 500 km of Sydney airspace, but [Balint] is working on expanding the coverage with the help of other plane spotters. If you’re willing to help [Balint] expand his coverage, be sure to drop him a line.

Of course, [Balint] is the guy who gave us a software radio source block for those cheap USB TV tuner dongles. Just a few days ago we saw these dongles receiving GPS data, so we’re very impressed with what these little boxes can do in the right hands. [Balint] says his Aviation Mapper application will work with any GNU Radio receiver, so it’s entirely possible to copy his work with a handful of TV tuner dongles.

After the break, there’s two videos of [Balint] sitting at the end of the runway near the Sydney airport watching arrivials come in right above his head and on his laptop. It’s very cool, but we’d be interested in an enterprising hacker in the New York City area copy [Balint]’s work.

There are devices on sale legally for around £500 that provide the same information. Also just like cars most planes (commercial) end up flying down well published airways, which are basically small lanes in the sky.

Um, this is already required, and on, all commercial aircraft, on botht he USA and Australia. It’s part of FAA’s new GPS system to reduce the RADAR. (Australia is also looking into a similar system.)

It still has some drawbacks – It is totally reliant on equipment on the aircraft, so if there’s a fault the plane could “Disappear” (Having a RADAR backup will solve that issue) And AFAIK ACAS, like TCAS, doesn’t inform ATC what it’s telling the pilots. So there’s still the potential for conflicting instructions to cause an Accident like the one in Europe a few years ago.

Finally, while this is very, very cool, the incorporation into Google Earth/Maps is re-inventing the wheel a bit, there are other projects like http://www.flightradar24.com/increase_coverage.php – Adding the SDR to already established projects like this may get more bang-for-buck.

They ignored their radar driven altimeter. Current ground radar has difficulty determining altitude at long range, and for altitude data relies on the transponders information. I would argue in that case that the pilots failed to recognize the failure of a common support system in the aircraft.

The radar in use at the time was designed to maintain separation. This radar doesn’t do a good job of detecting altitude. The transponders sending this information to ATC solves the problem. The further you can ‘see’ the less detail you can see with. These radars can see for 100s of miles. Close to the major airports we have radars that operate faster (most controller screens update about once every 15 seconds) and are able to detect altitude better, but are very short range.

@David Fletcher
This system works shockingly well. In the past 50 years, there have only been 10 mid air collisions in the US. Not a single one was between two ATCO controlled aircraft. ALL of them were between 2 General Aviation (think Cessna) aircraft, or involved GA or military aircraft hitting a controlled aircraft. 10 incidents in ~200 Million successful flights. Other higher risk factors and issues need research before we invest in this. MANY times more aircraft have run off the end of the runway.

Thank you to those that have installed the Google Earth Browser Plugin and tested it out!

If you found that the app didn’t finish loading (got stuck while ‘fetching trails’), then please try again as (I hope) I have fixed this (too much data in the pipe as returned trails were excessively fine-grained). Added bonus is that these cached trails should take far less time to add to the map.

I am waiting to get at least one of these dongles and wondering what kind of antenna to use for general purpose vertical polarization reception. Maybe a discone broadband antenna. Those whips that come with the dongles must have a huge amount of cable loss between them and the dongle. Also, the SWR will be so high that 3/4 of the signal will get lost and the feedline will be so mismatched that its part of the antenna.

How complicated would be to add input amplifier for those cheap usb tuners, to get some reasonable gain?
By default, it is even not so easy to receive dvb-t station, not mentioning other, much weaker signals.